IGS is adopting a new coordinate frame (IGS20) and file naming scheme as seen in this announcement: https://igs.org/news/igs20/.
As part of this change they are modifying the file naming scheme used for the GPS SP3 files (http://acc.igs.org/repro3/Long_Product_Filenames_v1.0.pdf). The GPS week and day of week in the file name have been replaced by UTC year and day of year.
Example previous Rapid name:
Example new Rapid name:
Example previous Ultrarapid name:
Example new Ultrarapid name:
The project I am working on saw a negligible difference in the results with the change in the coordinate frame. For GPS weeks 2222-2237, you can use data in https://cddis.nasa.gov/archive/gnss/products/WWWW/igs20/ (where WWWW is the GPS week) to compare the IGS20 coordinate frame data with the previous system.
CDDIS might need to update this page to reflect the new naming scheme: